Topamax is one of those drugs that treat a variety of problems. I am on Neuritin. It's used for helping frayed nerve endings behave and not to misfire so much; it helps with the pain. It was originally prescribed for siezures.
I was on Topamax briefly; but it caused too many adverse side effects so my doctor took me off of it.
Tresadone was origanlly prescribed for depression; but is used for a sleep aid.
Ambien has multiple uses; a sleep aid and also for Restless Legs Syndrome.